The National Center for Complementary and Alternative Medicine (NCCAM) recognizes the critical importance of training clinicians, including clinicians trained in complementary and alternative medicine (CAM), to become researchers, and encourages them to apply for this F32 National Research Service Award (NRSA). The proposed fellowship program is for a chiropractic physician to develop proficiency using state-of-the-art techniques for examining physiological aspects of pain processing such as quantitative sensory testing (QST) and neuroimaging, with a particular focus on functional magnetic resonance imaging (fMRI). The fellow will participate in research across several centers and laboratories at the University of Florida that examine biological, psychological, and societal influences on pain perception. Central to this training program is the primary mentor's NIH Funded R01-AT006334-01 project. This study measures biological (e.g. pain sensitivity, fMRI) and psychological (e.g. fear, beliefs, expectation) aspects of acute exercise-induced low back pain. The project also assesses the impact of spinal manipulative therapy on those biological and psychological endpoints and their relation to clinical measures of pain, disability and physical impairment. The research proposed in this application will be a part of and complement the larger study by collecting resting-state fMRI. The central hypothesis of this application is tht the cortical reorganization, initiated by increased neural activity following a muscular injury to the low back and associated with central sensitization, can be monitored by resting-state fMRI. This powerful tool for studying network mechanisms of brain functioning will be used to longitudinally assess functional connectivity between relevant brain regions, such as the primary and secondary somatosensory cortices, insula, anterior cingulated cortex, thalamus and periaqueductal grey. The Specific Aims are to: (1) Measure changes in synchronized neuronal activity across brain regions before, during and after a transient state of pain hypersensitivity, and (2) Measure the immediate effect of spinal manipulation on the synchronized neural activity. Through completion of this program, the fellow will have (1) gained an in- depth appreciation for a range of models and methods to assess pain perception involving physiological, psychological and environmental components of the pain experience, and (2) built a solid foundation to pursue a program of research evaluating underlying neurophysiological mechanisms of manipulative and body-based interventions and their clinical relevance. This fellowship training program for a chiropractic physician is appropriate for NCCAM's mission because it (1) focuses on a CAM intervention that is frequently provided to the American public by chiropractors for low back pain, and (2) investigates a potential neurophysiologic mechanism underlying pain relief, which is why the intervention is most frequently employed.